Interesting thoughts!

Therefore, the results of the new study support the idea that primitive life could potentially have evolved on Ganymede. This is because places where water and rock interact are important for the development of life. For example, some theories suggest that life arose on our planet within hot, bubbling seafloor vents. Before the new study, Ganymede's rocky seafloor was believed to be coated with ice--not liquid. This would have presented a problem for the evolution of living tidbits. The "Dagwood sandwich" findings, however, indicate something else entirely--the first layer on top of Ganymede's rocky core might be made up of precious, life-sustaining salty water.

However, it was little Enceladus that gave astronomers their greatest shock. Even though the existence of Enceladus has been known since it was discovered by William Herschel in 1789, its enchantingly weird character was not fully appreciated until this century. Indeed, until the Voyagers flew past it, little was known about the moon. However, Enceladus has always been considered one of the more interesting members of Saturn's abundantly moonstruck family, for a number of very good reasons. First of all, it is amazingly bright. The quantity of sunlight that an object in our Solar System reflects back is termed its albedo, and this is calculated primarily by the color of the object's ground coating. The albedo of the dazzling Enceladus is almost a mirror-like 100%. Basically, this means that the surface of the little moon is richly covered with ice crystals--and that these crystals are regularly and frequently replenished. When the Voyagers flew over Enceladus in the 1980s, they found that the object was indeed abundantly coated with glittering ice. It was also being constantly, frequently repaved. Immense basins and valleys were filled with pristine white, fresh snow. Craters were cut in half--one side of the crater remaining a visible cavity pockmarking the moon's surface, and the other side completely buried in the bright, white snow. Remarkably, Enceladus circles Saturn within its so-called E ring, which is the widest of the planet's numerous rings. Just behind the moon is a readily-observed bulge within that ring, that astronomers determined was the result of the sparkling emission emanating from icy volcanoes (cryovolcanoes) that follow Enceladus wherever it wanders around its parent planet. The cryovolanoes studding Enceladus are responsible for the frequent repaving of its surface. In 2008, Cassini confirmed that the cryovolanic stream was composed of ordinary water, laced with carbon dioxide, potassium salts, carbon monoxide, and a plethora of other organic materials. Tidal squeezing, caused by Saturn and the nearby sister moons Dione and Tethys, keep the interior of Enceladus pleasantly warm, and its water in a liquid state--thus allowing the cryovolcanoes to keep spewing out their watery eruptions. The most enticing mystery, of course, is determining exactly how much water Enceladus holds. Is there merely a lake-sized body of water, or a sea, or a global ocean? The more water there is, the more it will circulate and churn--and the more Enceladus quivers and shakes, the more likely it is that it can brew up a bit of life.

Jupiter is circled by a bewitching duo of moons that are potentially capable of nurturing delicate tidbits of life as we know it. Like its more famous sister-moon, Europa, Ganymede might harbor a life-loving subsurface ocean of liquid water in contact with a rocky seafloor. This special arrangement would make possible a bubbling cauldron of fascinating chemical reactions--and these reactions could potentially include the same kind that allowed life to evolve on our own planet!

If you want to measure our solar system, how would you do it? This simplest way is to measure it in light years. For those not familiar with the term, a light-year is the distance that light travels in a vacuum in one year. This is because the distances between stars is so huge that it is otherwise very challenging to imagine them. A light year is exactly 9,460,730,472,580.8 kilometers. Putting this into real world distances, the Milky Way is approximately 100,000 light-years across.

But what truly makes Enceladus so remarkable is that its habitable zone can be observed with relative ease by astronomers. Dr. Porco told the press on March 27, 2012 that "It's erupting out into space where we can sample it. It sounds crazy but it could be snowing microbes on the surface of this little world. In the end, it's the most promising place I know of for an astrobiology search. We don't even need to go scratching around on the surface. We can fly through the plume and sample it. Or we can land on the surface, look up and stick our tongues out. And voila... we have what we came for."

Most of the moons of our Solar System are intriguing, frigid, and dimly lit ice-worlds in orbit around the quartet of outer, majestic, gaseous giant planets that circle our Star, the Sun, from a great distance. In our quest for the Holy Grail of discovering life beyond our Earth, some of these icy moons are considered to be the most likely worlds, within our own Solar System, to host life. This is because they are thought to hide oceans of life-sustaining liquid water beneath their alien shells of ice--and life as we know it requires liquid water to emerge, evolve, and flourish. In April 2017, a team of planetary scientists announced that they have discovered the presence of hydrogen gas in a plume of material erupting from Enceladus, a mid-sized moon of the ringed, gas-giant planet Saturn, indicating that microbes may exist within the global ocean swirling beneath the cracked icy shell of this distant small world. Currently, two veteran NASA missions are providing new and intriguing details about the icy, ocean-bearing moons of the gas-giant planets, Jupiter and Saturn, further heightening scientific fascination with these and other "ocean worlds" in our Solar System--and beyond.